Inspired: Human evolution & obstetrics

8 June 2016

Sometimes provocative and always interesting, this series of shorter stories can be inspired by pretty much anything in Wellcome Collection and offers a quick insight into some of the themes we explore. This one comes from Rock Webb.

As an archaeologist I am particularly interested in the notion of becoming and being human. The study of human evolution fascinates me, as well as how hominid development has had a profound effect on our modern biological makeup. Take obstetrical adaptation for example. The display of a whole array of forceps in our Medicine Man gallery reminds us how giving birth has become so medicalised. I would like to offer one view on this topic.

[object Object]

Forceps on display in our Medicine Man gallery.

Anatomically speaking, humans are not particularly suited to giving birth. Evidence for this can be seen in the frequency and nature in which we encounter obstetric problems. Neonatal and maternity mortality rates are high. Modern day births are highly controlled, highly medicalised and highly reliant on technological intervention. Startlingly, one in three babies in the USA are born via caesarean. Australian midwives find it near impossible to get insurance cover for home births. The chief cause seems to be a problematic birth canal; we have to search our deep ancestral past to find out why.

The discovery in 1974 of ‘Lucy’, a 3.2 million year old hominid Australopithicus afarensis, provided us with a critical point of reference in our understanding of human evolution. Her fossilised remains include enough of the hip and thigh bones to provide solid evidence of the move to bipedalism and the potential consequences of this adaptation. A later, more complete skeletal discovery, ‘Selam’, has shown that brain development from child to adult is rather slow, indicating an extended childhood. This is significant and distinctively human.

[object Object]

Delivery of foetus with forceps around head.

Human obstetrics is unique in the animal world: human anatomical evolution has imposed a somewhat alternative gestation-birth pattern. The permanent adaptation to upright walking has necessitated a pelvic arrangement with a characteristically narrow birth canal. Babies have to be expelled at a time when they can fit through and, thus, are actually born ‘too early’ at nine months. This would explain the excessive degree to which newborn babies are vulnerable. They are unable to gain nutrition, warmth and protection without the intervention of another human, i.e an innate inability to self-care; an extended childhood.

Giving birth is also a vulnerable time for the mother and, again, the intervention of others is required. No other mammal seeks such help during childbirth, but then, no other mammal has such a compact pelvis. Three million years of evolution might be perfect for upright walking, but seemingly poor for giving birth.

Rock is a Visitor Experience Assistant at Wellcome Collection.